Hearing loss is the most common sensory disorder in the US, afflicting over 36 million people; thus, identification of modifiable risk factors is a vital public health issue. Strikingly, there are only limited prospective data on common and potentially modifiable risk factors for this highly prevalent, disabling condition. In addition to noise, factors potentially associated with risk of hearing loss include analgesics, vitamins, alcohol, menopausal status and postmenopausal hormone use. Aspirin, acetaminophen and ibuprofen are the three most commonly used drugs in the U.S. The ototoxic effects of high dose salicylates are well-known. Our preliminary studies in men found an increased risk of hearing loss with regular moderate use of aspirin, NSAIDs, and acetaminophen;however, this has not been prospectively studied in women. Vitamins, such as folate, A, C, D, and E, may play important roles in maintenance of hearing. Alcohol intake may have a variable impact on hearing, depending on the level of use. Additionally, estrogen may play a role in hearing function, thus menopausal status and postmenopausal hormone use may have important implications for hearing loss. We will examine these issues prospectively in large ongoing cohort studies involving over 150,000 women (Nurses'Health Studies I and II). To identify factors that can be modified at an early stage to conserve hearing, will examine audiometrically measured change in hearing sensitivity over 3 years in a subset of 3000 women in NHS II with either no or mild hearing loss. The secondary outcome will be selfreported professionally diagnosed hearing loss in the entire study population. We expect more than 5000 incident cases in each female cohort to be identified and confirmed by a supplementary questionnaire. We will use a multidisciplinary approach to examine the association between these common factors and the risk of hearing loss. PUBLIC HEALTH RELEVANCE: Hearing loss is a very common sensory disorder in the US, afflicting over 36 million people; thus, identification of factors that can be modified to reduce the likelihood of developing hearing loss is a vital public health issue. Using several ongoing large prospective studies involving more than 150,000 women, we will examine whether common pain relievers, vitamins, alcohol, menopausal status and postmenopausal hormone use are associated with the risk of developing hearing loss. We will also perform hearing tests in 3000 women to examine whether these factors influence change in hearing sensitivity.